Bionic optic nerve based on perovskite (CsPbBr 3) quantum-dots / 生物医学工程学杂志

The bionic optic nerve can mimic human visual physiology and is a future treatment for visual disorders. Photosynaptic devices could respond to light stimuli and mimic normal optic nerve function. By modifying (Poly(3,4-ethylenedioxythio-phene):poly (styrenesulfonate)) active layers with all-inorganic perovskite quantum dots, with an aqueous solution as the dielectric layer in this paper, we developed a photosynaptic device based on an organic electrochemical transistor (OECT). The optical switching response time of OECT was 3.7 s. To improve the optical response of the device, a 365 nm, 300 mW·cm -2 UV light source was used. Basic synaptic behaviors such as postsynaptic currents (0.225 mA) at a light pulse duration of 4 s and double pulse facilitation at a light pulse duration of 1 s and pulse interval of 1 s were simulated. By changing the way light stimulates, for example, by adjusting the intensity of the light pulses from 180 to 540 mW·cm -2, the duration from 1 to 20 s, and the number of light pulses from 1 to 20, the postsynaptic currents were increased by 0.350 mA, 0.420 mA, and 0.466 mA, respectively. As such, we realized the effective shift from short-term synaptic plasticity (100 s recovery of initial value) to long-term synaptic plasticity (84.3% of 250 s decay maximum). This optical synapse has a high potential for simulating the human optic nerve.

Effect of exogenous CdS nanoparticle on the growth of Escherichia coli / 生物工程学报

Semiconductor nanoparticles generate photoelectrons and photo-induced holes under light excitation, and thus may influence the growth of microbial cells. The highly oxidative holes may severely damage the cells, while the photoelectrons may promote microbial metabolism. In this study, we evaluated the effect of exogenous cadmium sulfide (CdS) nanoparticles on bacterial growth using OD600 and colony forming unit (CFU) as indicators. The oxidase activities, the concentration of pyruvate and malondialdehyde, and the expression of relevant genes assessed by real-time fluorescent quantitative PCR were analyzed to investigate the effect of excited CdS on cellular metabolism. The results showed that the OD600 and pyruvate accumulation of E. coli increased by 32.4% and 34.6%, respectively, under light conditions. Moreover, the relative expression level of the division protein gene ftsZ was increased more than 50%, and the tricarboxylic acid cycle pathway gene icdA and gltA increased by 86% and 103%, respectively. The results indicated that photoelectrons could be used by microorganisms, resulting in promoted growth and metabolism. This study gives a deep insight into the interaction between nanoparticles and bacteria.

Compliance of patients to DOTS tuberculosis treatment strategy in a South-East Nigeria Teaching Hospital

Introduction: Tuberculosis ranks the second highest cause of adult mortality after HIV in the world. The Directly Observed Treatment Short course (DOTS) strategy is aimed at following up on patients' adherence to treatment regimen. Objectives: To assess the level of compliance of patients to the DOTS strategy. Materials and Methods: A retrospective study of patients seen at the University of Nigeria Teaching Hospital from January 2013 to April 2015. Relevant information was collected from patients' folders. Data analysis was with the SPSS and results represented in tables. Results: 111 (50%) patients were compliant with their DOTS treatment plan while 107 (41.3%) were non-compliant. Ninety-two patients (41.4%) were successfully treated and discharged home, 7 patients (3.2%) referred to other centers. The proportion of patients regarding their marital status, occupation, educational level and address that was compliant to the DOTS TB reflected varied patterns. Conclusion/ Recommendations: The study reflected poor to average compliance to DOTS. There is a need for creation of more DOTS centers; regular surveys and updates on DOTS TB strategy should be the norm rather than the exception

Simple synthesis of photoluminescent carbon dots from a marine polysaccharide found in shark cartilage

BACKGROUND: For more than a decade, water-soluble, eco-friendly, biocompatible, and low-toxicity fluorescent nanomaterials have received considerable attention for their numerous in vivo and in vitro applications in biomedical imaging, disease diagnostics, and environmental monitoring. Owing to their tunable photoluminescence properties, carbon-based luminescent nanomaterials have shown great potential in bioimaging, photocatalysis, and biosensing among other applications. RESULTS: Marine environments provide excellent resources for the fabrication of these nanomaterials, because many marine organisms contain interesting trigger organic compounds that can be used as precursors. Herein, we synthesize multi-color emissive carbon dots (CDs) with an intrinsic photoluminescence quantum yield of 20.46%. These nanostructures were achieved through the one-step hydrothermal treatment of marine polysaccharide chondroitin sulfate, obtained from shark cartilage, in aqueous solution. CONCLUSIONS: We successfully demonstrate the low toxicity of our marine resource-derived CDs in zebrafish, and provide an initial assessment of their possible use as a bioimaging agent. Notably, the newly synthesized CDs localize in the intestines of zebrafish larvae, thereby indicating their biocompatibility and potential use as in vivo dyes.

Monitorização de células-tronco mesenquimais injetadas via retrobulbar próximas ao nervo óptico lesados de coelhos / Monitoring of stem cells from adipose tissue injected via retrobulbar next to previously injured optic nerve of rabbits

Resumo Objetivo: Verificar a presença das células-tronco mesenquimais (MSC) na área próxima ao nervo óptico de coelhos previamente lesado com álcool absoluto. Métodos: Os 12 coelhos da raça Nova Zelândia foram distribuídos em 2 lotes. Após sedação, cada olho do animal recebeu uma injeção retrobulbar de 1 ml de álcool absoluto em um dos olhos e de 1 ml de solução fisiológica 0,9% (SF) no olho contralateral. Após 15 dias deste procedimento inicial todos os olhos dos animais pertencentes ao lote A, receberam via retrobulbar, uma solução contendo MSC de tecido adiposo humano e previamente marcadas com Qdots,. Todos os olhos dos animais do lote B receberam solução PBS. Resultados: Após 15 dias desta última aplicação os animais foram sacrificados e as lâminas foram analisadas. A presença das MSC foi observada em 100% dos olhos dos animais do lote A. Conclusão: Os resultados sugerem que a marcação prévia das MSC com Qdots permitiu o acompanhamento das mesmas na região aplicada e em áreas mais internas do nervo óptico. A permanência de MSC após 15 dias de aplicação ao redor do nervo óptico sugere a viabilidade e possível participação das mesmas no processo de regeneração do tecido lesado. Nas condições deste estudo, a via de aplicação retrobulbar permitiu a mobilização das células tronco do local de aplicação até áreas centrais dos nervos ópticos nos animais do lote A, sugerindo que esta poderá ser uma via de acesso eficaz para as MSC no processo de regeneração de neuropatias ópticas.

Abstract Obtective: To verify the presence of mesenchymal stem cells (MSC) in the area close to the optic nerve of previously injured with absolute alcohol. Methods: Twelve New Zealand breed rabbits were divided into two groups, and after sedation, each eye of the animal received a retrobulbar injection of 1 ml of absolute ethanol in one eye, and 1 ml of physiological solution 0.9 % (PS) in the contralateral eye. After 15 days all eyes of animals belonging to group A, received via retrobulbar a solution containing MSCs from human adipose tissue (AT) and previously marked with Qdots, while all eyes of animals from group B received solution containing PBS. Results: The presence of MSC was observed in 100% of the eyes of the animals of group A and the more central areas near and into the optic nerve. Conclusion: The results suggest that the appointment of MSC with Qdots allowed their follow-up applied in the region and in the inner areas of the optic nerve. The MSC permanence after 15 days of application around the optic nerve suggests the feasibility and possible involvement of the same during the damaged tissue regeneration process. Under the conditions of this study, the route of retrobulbar application and the presence of the stem cells to the central areas of the optic nerves in animals of group A, suggests that this might be an effective approach for MSCs in regeneration process of optic neuropathies.

Synthesis of transdermal aloesin loaded zinc oxide nanoparticles and its inhibitory effect on the activity of tyrosinase / 生物医学工程学杂志

Zinc oxide quantum dots (ZnO QDs) were synthesized by gel-sol method and employed as the transdermal aloesin (Alo) carriers. ZnO QDs were surface-functionalized with amino using aminopropyltriethoxysilane (APTES). Alo was covalently bonded on the surface of ZnO QDs via N,N'-carbonyldiimidazole to obtain Alo NPs, which were characterized by transmission electron microscope (TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR) and thermal gravimetric analyzer (TGA). TEM images showed that ZnO QDs were analogously sphere and monodisperse with a reasonably narrow size distribution, of which was around 4 nm. The size of Alo NPs increased to around 8 nm due to the surface modification. The intense bands at around 3 400 cm and 1 200 cm in the FTIR spectrum of Alo NPs from the vibration of -OH indicated the linkage of Alo on the surface of ZnO QDs. The results of TGA analysis showed that the mass ratio of ZnO QDs and Alo were 39.27% and 35.14%, respectively. The penetration of Alo NPs was much higher than raw Alo according to the passive penetration experiments with Franz-type diffusion cells instrument using full-thickness cavy skin, which manifested the improvement of the penetration for Alo delivered by ZnO QDs. The pH-controlled drug release behavior was investigated. At pH 7.4, only a small amount of Alo (1.45% ± 0.21%) had been released after 2 h. In contrast, as incubation at pH 5.0 of which pH was similar to endosomal environment, Alo was released very fast (87.63% ± 0.46% in 2 h) from Alo NPs, confirming that Alo NPs could response to the pH and realize the intracellular drug release. The inhibitory effect of Alo NPs on tyrosinase was in a dose dependent manner. When the concentration of Alo NPs was 12.5 μg/mL, the inhibition rate was up to 40.32% ± 1.57%. All the results show that the Alo NPs hold a great potential in transdermal tyrosinase inhibition.

Sistemas de nanopartículas poliméricas II: estructura, métodos de elaboración, características, propiedades, biofuncionalización y tecnologías de auto-ensamblaje capa por capa (layer-by-layer self-assembly) / Polymeric nanoparticle systems: structure, elaboration methods, characteristics, properties, biofunctionalization and self-assembly layer by layer technologies

Los materiales poliméricos han sido ampliamente investigados para aplicaciones biomédicas, teniendo especial relevancia cuando se encuentran en forma de micro- y nano-partículas. Últimamente se ha ampliado su campo de aplicación al ser conjugados con péptidos y ácidos nucleicos, por lo tanto, el interés en el estudio de este tipo de materiales, así como también en la formulación de nanoestructuras funcionalizadas como materiales, dispositivos y vehículos de transporte de agentes terapéuticos ha aumentado. Las recientes investigaciones en nanosistemas se inspiran en fenómenos naturales que estimulan la integración de señales moleculares y la mimetización de procesos a nivel celular, de tejidos y órganos. Tecnológicamente, la capacidad de obtener nanoestructuras esféricas mediante la combinación de materiales que presenten propiedades distintas a las que ningún otro material individual posee por sí solo, es lo que hace que las nanocápsulas sean particularmente atractivas. Las potenciales ventajas de los sistemas de nanopartículas de tipo polimérico se destacan a lo largo de cada parte de este artículo de revisión. El presente artículo aborda los aspectos más relevantes sobre la estructura, composición y algunos métodos de elaboración de los sistemas nanoparticulados. Además, expone algunos de los trabajos más recientes, centrados en sistemas de nanopartículas basados en polímeros dirigidos a la administración de agentes, publicados en artículos especializados de investigación y revisiones durante los últimos años.

Polymeric materials have been extensively investigated for biomedical applications including micro- and nanoparticles. Modern advances have broadened horizons for application with peptides and nucleic acids. Therefore, interests increased in the formulation of materials, devices and vehicles for transporting therapeutic agents in functionalized nanostructures. Recent nano-systems are inspired by natural phenomena that stimulate the integration of molecular signals and the mimicking of natural cellular processes, at tissue and organ levels. Technologically, the ability to obtain spherical nanostructures, which combine different properties, that no other single material possesses on its own, makes nanocapsules particularly attractive. Potential advantages over polymer nanoparticulate systems are highlighted throughout each part of this review article. Here, we address the most relevant aspects of structure, composition and methods of formulation of nanoparticulate systems. In addition, we outline some of the more recent works focusing on nanosized preparations, based on agent-directed polymers, found in specialized research articles that have emerged in the recent years.

Sistemas de nanopartículas poliméricas i: de biodetección y monitoreo de glucosa en diabetes a bioimagen, nano-oncología, terapia génica, ingeniería de tejidos / regeneración a nano-odontología / Polymer nanoparticle systems: from biodetection and glucose monitoring in diabetes to bioimaging, nano-oncology, gene therapy, tissue engineering / regeneration to nano-dentistry

Nanotecnología es la ciencia que involucra la síntesis de materiales en escala entre 1-100 nm (nanomateriales) es aplicable en diferentes áreas tales como medio ambiente, electrónica, alimentos, energía, entre otros. Los campos que serán relevantes dentro de esta revisión y explicados en detalle son la nanomedicina y la nano-odontología. Actualmente, en estas áreas los tres principales temas en desarrollo son específicamente en el sub-área de la nanobiotecnología y corresponden a: sensorización (biosensores/biodetección), diagnóstico (biomarcadores/bioimagen) y transportes de genes, proteínas o fármacos (sistemas de intercambio controlado en blancos sistémicos versus localizados). También se han presentado avances en bioaplicaciones como modelamientos de membranas, marcaje celular, entrega de agentes a blancos específicos, estrategias para prevención de enfermedades, ingeniería de tejidos, regeneración de órganos, estrategias de inmunoensayos y nano-oncología. Este artículo de revisión pretende abordar algunos de los aportes más relevantes, que tienen algunos de los trabajos recientes, sobre los sistemas de nanopartículas, principalmente aquellos dirigidos a terapias en áreas como diabetes, nano-oncología, terapia de fármacos y genes, mediante la técnica layer-by-layer y autoensamblado, muy utilizados también en ingeniería de tejidos y regeneración tisular, junto a un breve resumen de los avances que existen en el campo de la nano-odontología.

Nanotechnology is the science that involves the synthesis of materials in scale between 1-100 nm (nanomaterials) and is applicable in different areas such as environment, electronics, food, energy, among others. The fields that will be relevant within this review and explained in detail are nanomedicine and nano-dentistry. Currently, in these areas, the three main topics under development are specifically in the sub-area of nanobiotechnology and correspond to: sensorization (biosensors / biosensing), diagnostics (biomarkers / bioimaging) and transport of genes, proteins or drugs (exchange systems) controlled in systemic versus localized targets). Advances have also been presented in bioapplications such as membrane modeling, cell marking, delivery of agents to specific targets, strategies for disease prevention, tissue engineering, organ regeneration, immunoassay strategies and nano-oncology. This review article aims to address some of the most relevant contributions, some of the recent work, on nanoparticle systems, mainly those aimed at therapies in areas such as diabetes, nanooncology, drug and gene therapy, through the layer-by-layer and self-assembled technique, also widely used in tissue engineering and tissue regeneration, together with a brief summary of the advances that exist in the field of nano-dentistry.

Brain Theranostics and Radiotheranostics: Exosomes and Graphenes In Vivo as Novel Brain Theranostics / 대한핵의학회잡지

Brain disease is one of the greatest threats to public health. Brain theranostics is recently taking shape, indicating the treatments of stroke, inflammatory brain disorders, psychiatric diseases, neurodevelopmental disease, and neurodegenerative disease. However, several factors, such as lack of endophenotype classification, blood-brain barrier (BBB), target determination, ignorance of biodistribution after administration, and complex intercellular communication between brain cells, make brain theranostics application difficult, especially when it comes to clinical application. So, a more thorough understanding of each aspect is needed. In this review, we focus on recent studies regarding the role of exosomes in intercellular communication of brain cells, therapeutic effect of graphene quantum dots, transcriptomics/epitranscriptomics approach for target selection, and in vitro/in vivo considerations.

In vivo tracking of adipose tissue grafts with cadmium-telluride quantum dots

BACKGROUND: Fat grafting, or lipofilling, represent frequent clinically used entities. The fate of these transplants is still not predictable, whereas only few animal models are available for further research. Quantum dots (QDs) are semiconductor nanocrystals which can be conveniently tracked in vivo due to photoluminescence. METHODS: Fat grafts in cluster form were labeled with cadmium-telluride (CdTe)-QD 770 and transplanted subcutaneously in a murine in vivo model. Photoluminescence levels were serially followed in vivo. RESULTS: Tracing of fat grafts was possible for 50 days with CdTe-QD 770. The remaining photoluminescence was 4.9%±2.5% for the QDs marked fat grafts after 30 days and 4.2%± 1.7% after 50 days. There was no significant correlation in the relative course of the tracking signal, when vital fat transplants were compared to non-vital graft controls. CONCLUSIONS: For the first-time fat grafts were tracked in vivo with CdTe-QDs. CdTe-QDs could offer a new option for in vivo tracking of fat grafts for at least 50 days, but do not document vitality of the grafts.

Current Status and Future Direction of Nanomedicine: Focus on Advanced Biological and Medical Applications / 대한핵의학회잡지

Nanotechnology is the engineering and manipulation of materials and devices with sizes in the nanometer range. Colloidal gold, iron oxide nanoparticles and quantum dot semiconductor nanocrystals are examples of nanoparticles, with sizes generally ranging from 1 to 20 nm. These nanotechnologies have been researched tremendously in the last decade and this has led to a new area of “nanomedicine” which is the application of nanotechnology to human healthcare for diagnosis, monitoring, treatment, prediction and prevention of diseases. Recently progress has been made in overcoming some of the difficulties in the human use of nanomedicines. In the mid-1990s, Doxil was approved by the FDA, and now various nanoconstructs are on the market and in clinical trials. However, there are many obstacles in the human application of nanomaterials. For translation to clinical use, a detailed understanding is needed of the chemical and physical properties of particles and their pharmacokinetic behavior in the body, including their biodistribution, toxicity, and biocompatibility. In this review, we provide a broad introduction to nanomedicines and discuss the preclinical and clinical trials in which they have been evaluated.

Effects of Canine and Murine Mesenchymal Stromal Cell Transplantation on Peripheral Nerve Regeneration

BACKGROUND AND OBJECTIVES: Maintaining a permissive microenvironment is essential for adequate nerve regeneration. Cell-based therapy has the potential based cell replacement and promotion of axonal growth. The adipose tissue derived mesenchymal stromal cells (Ad-MSC) attract interest because neuroregenerative and anti-inflammatory properties. The aim of this study was to evaluate the effects of canine and murine Ad-MSC transplantation on the sciatic nerve regeneration. METHODS: Forty Wistar rats were divided randomly into: control group - CG (n=8); denervated group - DG (n=8); decellularized vein group - VG (n=8); decellularized vein+canine MSC–cMSC (n=8); descellularized vein+murine MSC–mMSC (n=8). After 10-mm nerve gap, the tubulation technique was performed with decellularized vein filled with 10⁶ MSC labeled with quantum dots (Qtracker 665®). The sciatic nerve functional index (SFI) and electroneuromyography (ENMG) measurements were carried and morphometric and immunohistochemistry analysis of the tissue. RESULTS: The SFI values were higher in the cMSC and mMSC groups at day 27 (p<0.020) and day 35 (p<0.011). The ENMG analysis also revealed better results in the mMSC group. Density, number, and total area of the fibers were increased in the mMSC and cMSC groups. Brain-derived neurotrophic factor BDNF and S-100 protein positive immunoreactivity showed a higher expression for both in the nerve of the mMSC and cMSC groups. The MSC labeled with quantum dots were detected at day 35, indicating neuronal survival long after the nerve damage. CONCLUSIONS: Murine and canine Ad-MSC associated with decellularized vein scaffold had positive effects on sciatic nerve regeneration in rats.

The effects of graphene quantum dots on hematopoietic system in rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study the effects of graphene quantum dots (GQDs) on hematopoietic system in rats.</p><p><b>METHODS</b>Thirty male SD rats were randomly divided into three groups (n = 10): control group, high dose group (10 mg/kg · d), low dose group (5 mg/kg · d), The rats in experimental group were intravenous injected with GQDs for 28 days and those in control group were injected with normal saline at the same volume. Routine blood and the function of liver and kidney were detected by instrument analysis. The cycle and apoptosis of bone marrow mononuclear cells (BMCs) were detected by FCM. The other three only healthy male SD rat bone marrow mononuclear cells (BMCs) were cultured by joining GQDs for 24 h, 48 h,72 h in vitro, the proliferation was assayed by CCK-8, the content of granulocyte macrophage colony stimulating factor (GM-CSF) from cultural supernatants were detected by ELISA.</p><p><b>RESULTS</b>The amount of red blood cell and concentration of hemoglobin from experimental group were increased significantly compared with those of control groups (P < 0.05), the concentration of triglyceride and high density lipoprotein were decreased. DNA synthesis period was prolonged (P < 0.01), there was no significant difference in apoptosis. BMCs were promoted proliferation clearly after using GQDs for 72 h (P < 0.05). The content of GM-CSF was increased (P < 0.01) .</p><p><b>CONCLUSION</b>GQDs may promote hematopoietic function in rats.</p>

Prevalência de diagnóstico médico de asma em adultos brasileiros: Pesquisa Nacional de Saúde, 2013 / Prevalence of asthma medical diagnosis among Brazilian adults: National Health Survey, 2013

RESUMO: Objetivo: Estimar a prevalência de diagnóstico médico de asma na população adulta brasileira (≥ 18 anos). Métodos: Estudo transversal de base populacional com dados da Pesquisa Nacional de Saúde (PNS), de 2013; processo amostral por conglomerado com três estágios de seleção: setor censitário, domicílio e indivíduo. Calculou-se a prevalência e intervalo de confiança de 95% (IC95%) do desfecho "diagnóstico médico de asma" relatado pelo entrevistado e sua distribuição conforme variáveis demográficas, socioeconômicas, macrorregiões e zona urbana ou rural do país. Ainda foi investigado o manejo da asma naqueles que responderam afirmativamente sobre o diagnóstico médico; as análises foram ponderadas. Resultados: Foram entrevistados 60.202 adultos. A prevalência do diagnóstico médico de asma foi de 4,4% (IC95% 4,1 - 4,7), maior no sexo feminino, nos de cor branca, com maior escolaridade e moradores na região Sul; entre aqueles com diagnóstico médico, observou-se percentual elevado (38,2%) de crises de asma nos últimos 12 meses, com cerca de 80% usando medicação e 15% com limitação severa às atividades diárias. Conclusões: Apesar da estabilidade da prevalência da asma comparada a estudos anteriores no país, ainda são necessárias políticas para melhor manejo da doença.

ABSTRACT: Objective: To estimate the prevalence of asthma medical diagnosis among the adult Brazilian population (aged ≥ 18 years). Methods: This is a cross-sectional, population-based study from the 2013 National Health Survey (NHS); it is a sampling cluster process with three stages of selection: census tracts, households, and individuals. The prevalence and 95% confidence interval for the outcome "asthma medical diagnosis" reported by the interviewed subjects were calculated, besides its distribution according to demographic and socioeconomic variables, macroregions, and urban or rural area of the country. Management of the disease was also evaluated among those who reported asthma medical diagnosis and the analyses were weighted. Results: A total of 60,202 adults were interviewed. The prevalence of asthma medical diagnosis was 4.4% (95%CI 4.1 - 4.7), and it was higher among the female subjects, the white skin-colored subjects, those with higher educational level, and those who lived in the south of Brazil. Among those who reported asthma medical diagnosis, a high percentage of asthma attacks were seen in the last 12 months, with around 80% using medication and about 15% referring severe limitation to their daily activities. Conclusions: Although it seems there is asthma diagnosis stability in the country when compared with other researches, we still need public policies for improving the disease management.

An evaluation of Avogadro’s number in the light of HRTEM and EDS studies of high dilutions of Ferrum metallicum 6, 30, 200, 1M, 10M and 50Mc

As a therapeutic tool high dilutions (HDs) are always at the center of controversies due to problems to validate them as a function of Avogadro’s number. Nevertheless, homeopathy is practiced around the world as a complementary and alternative medicine. The present study sought to evaluate HDs of homeopathic drug Ferrum metallicum (Ferr) 6, 30, 200, 1M, 10Mc and 50Mc, all of which except for 6c surpass Avogadro’s number. Using HRTEM and EDS it was conclusively shown that: 1) all the investigated HDs of Ferr contained plenty of nanoparticles (NPs); 2) the size of NPs were within the quantum dots (QD) size range, except for 50Mc, in which larger particles were found (12.61nm); 3) NPs contained iron in various weight percentages; 4) the weight percentage of iron was highest in HDs 10Mc and 50Mc...

Current Status of Optical Imaging for Evaluating Lymph Nodes and Lymphatic System

Optical imaging techniques use visual and near infrared rays. Despite their considerably poor penetration depth, they are widely used due to their safe and intuitive properties and potential for intraoperative usage. Optical imaging techniques have been actively investigated for clinical imaging of lymph nodes and lymphatic system. This article summarizes a variety of optical tracers and techniques used for lymph node and lymphatic imaging, and reviews their clinical applications. Emerging new optical imaging techniques and their potential are also described.

Toxicity of Graphene Quantum Dots in Zebrafish Embryo / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To evaluate the bio-safety of graphene quantum dots (GQDs), we studied its effects on the embryonic development of zebrafish.</p><p><b>METHODS</b>In vivo, biodistribution and the developmental toxicity of GQDs were investigated in embryonic zebrafish at exposure concentrations ranging from 12.5-200 μg/mL for 4-96 h post-fertilization (hpf). The mortality, hatch rate, malformation, heart rate, GQDs uptake, spontaneous movement, and larval behavior were examined.</p><p><b>RESULTS</b>The fluorescence of GQDs was mainly localized in the intestines and heart. As the exposure concentration increased, the hatch and heart rate decreased, accompanied by an increase in mortality. Exposure to a high level of GQDs (200 μg/mL) resulted in various embryonic malformations including pericardial edema, vitelline cyst, bent spine, and bent tail. The spontaneous movement significantly decreased after exposure to GQDs at concentrations of 50, 100, and 200 μg/mL. The larval behavior testing (visible light test) showed that the total swimming distance and speed decreased dose-dependently. Embryos exposed to 12.5 μg/mL showed hyperactivity while exposure to higher concentrations (25, 50, 100, and 200 μg/mL) caused remarkable hypoactivity in the light-dark test.</p><p><b>CONCLUSION</b>Low concentrations of GQDs were relatively non-toxic. However, GQDs disrupt the progression of embryonic development at concentrations exceeding 50 μg/mL.</p>

Periodoncia y mecánica cuántica / Periodontics and quantum mechanics

A la luz de los conocimientos actuales relativos al mundo de la física, se analiza la etiología de la enfermedad periodontal, que podría condensarse en la palabra incertidumbre.

Fluorescent carbon dots and the application in biomedicine / 药学学报

As a new type of carbon nanomaterials, fluorescent carbon dots (fluorescent CDs) have many advantages when compared with the traditional fluorescent probes. They are photoluminescence stable and resistance to photo bleaching. Moreover, they are excellent in biocompatibility, low-toxic and easy to modify. All these above make them a promising optical image material as a probe in optical image. This article reviews structure, the common carbon sources, the preparation methods, and the light-emitting principles of the carbon dots. We also introduce the research progress of fluorescent carbon dots in biomedicine, and the problems need to be resolved in the study of fluorescent CDs.

Preparation and characterization of tumor targeted CdTe quantum dots modified with functional polymer / 药学学报

N-acetyl-L-cysteine (NAC) capped quantum dots (QDs) were synthesized by a hydrothermal method and coated with 2-amino-2-deoxy-D-glucose (DG), polyethylene glycol (PEG), and 9-D-arginine (9R). The optical properties, morphology and structure of 9R/DG-coated CdTe QDs were characterized by ultraviolet-visible spectrometry, fluorescence spectrum, Fourier transform infrared (FTIR), proton nuclear magnetic resonance (1H NMR), liquid chromatography-mass spectrometer (LC-MS), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and transmission electron micrographs (TEM). Furthermore, the biocompatibility, tumor targeted ability and transmembrane action of 9R/DG-coated CdTe QDs were studied. Results indicated that 9R/DG-coated CdTe QDs was constructed successfully by ligand exchange. The 9R/DG-coated CdTe QDs with the size of 8-10 nm had good dispersity and the absorbance and fluorescence peaks of CdTe QDs after modification were red shifted from 480 nm to 510 nm and 627 nm to 659 nm, respectively. In addition, the CdTe QDs modified by PEG, DG and 9R displayed good biocompatibility, high targeted ability to the cancer cells with glucose transporter type 1 (GLUT1) receptor high expression and obvious transmembrane ability.